KR101447945B1 - Process for preparing a honeycomb catalyst for reducing nitrogen oxides using zeolite - Google Patents

Abstract

TECHNICAL FIELD The present invention relates to a technique for converting an exhaust gas containing nitrogen oxides (NOx) containing NO, NO ₂ , and N ₂ O into N ₂ and H ₂ O through a catalytic reaction by injecting a reducing agent such as ammonia or urea More particularly, the present invention relates to a method for producing a catalyst for reducing nitrogen oxides, comprising the steps of: (a) mixing shoebohemite, distilled water and a pH adjuster, Peptizing the inorganic binder to obtain an inorganic binder; (b) kneading the zeolite, the inorganic binder, the organic binder and the distilled water to obtain a dough; (c) extruding the dough into an extrudate having through-pores having a regular structure; And (d) drying the extruded body followed by heat treatment.

Exhaust gas, honeycomb, catalyst, nitrogen oxide, extrusion

Description

FIELD OF THE INVENTION [0001] The present invention relates to a method for producing a honeycomb type catalyst for reducing nitrogen oxides using zeolite,

TECHNICAL FIELD The present invention relates to a technique for converting an exhaust gas containing nitrogen oxides (NOx) containing NO, NO ₂ , and N ₂ O into N ₂ and H ₂ O through a catalytic reaction by injecting a reducing agent such as ammonia or urea And a method for producing a catalyst for purifying exhaust gas.

In recent years, there has been increasing concern worldwide of air pollution due to the industrial release of toxic oxides of nitrogen, sulfur and carbon. Due to these concerns, government departments have put restrictions on the allowable emissions of one or more of these pollutants, and regulations are becoming more stringent. Particularly, the nitrogen-based oxide is harmful per se, but it is a point at which the second-order pollutants are generated because of the photochemical action in the atmosphere, and thus the treatment is desired.

Conventionally, a catalyst having a high N ₂ reduction ratio among the catalysts used for the treatment of exhaust gas containing nitrogen-based oxides has been reported in which a metal such as Cu is sulfated and supported on a silica carrier (Japanese Patent Laid- In this catalyst, there is a disadvantage in that a volatile sulfur compound must be added to the exhaust gas in order to keep the metal in a sulfated state during the reaction, and when vanadium oxide, tungsten oxide (Japanese Patent Application Laid-Open No. 2001-293480). However, there is a problem in that the activity of the catalyst is rapidly lowered at a high temperature (400 ° C or higher), and there is a problem in that the use of the catalyst is limited due to the toxicity of vanadium .

In the case of using a zeolite as a carrier or a zeolite whose main component is a zeolite in which a metal having an activity to nitrogen oxide is substituted, it is used in a spherical, columnar, granular or honeycomb form. However, since the zeolite powder itself has a significantly low plasticity and sintering property, it is very important to form a molded article having a high specific surface area which is not destroyed by cracks during the manufacture of a zeolite carrier or a zeolite catalyst. It is progressing.

For example, an inorganic binder such as natural clay, bentonite, kaolin, colloidal silica, or a cellulose-based organic binder is added (US Patent No. 5116586) for forming and firing zeolite, but a relatively large amount of inorganic It is necessary to add a binder (natural clay), and the zeolite ratio of the prepared zeolite carrier or zeolite catalyst is reduced, thereby significantly degrading the performance of the catalyst.

In particular, in the case of a honeycomb type zeolite carrier or zeolite catalyst which can have a high specific surface area, since the internal pores passing through the molded body are regularly formed, a high formability and high physical strength There is a difficulty that the production is particularly difficult. Due to such a difficulty, wash coat type zeolite prepared by wet-milling catalytic materials having activity to zeolite and nitrogen oxide and coating the surface of the honeycomb structure was mainly used. However, in case of wash coat type zeolite, the removal efficiency of nitrogen oxide per unit volume is lower than that of honeycomb type zeolite extrudate, and the removal efficiency of nitrogen oxide is drastically decreased due to the damage of catalyst due to erosion in long term use.

Conventional techniques for solving difficulties in molding using zeolite as a main component include adding a polysaccharide having heat coagulability to zeolite as a base and forming a honeycomb form by adding starch minerals or inorganic fibers selectively, (Japanese Laid-Open Patent Publication No. 1995-053208), a method of mixing a salt-treated mesoporous zeolite with pseudobohemite, an organic binder, a plasticizer and a lubricant, followed by a low-temperature aging process A manufacturing method of forming a honeycomb shape followed by drying and high-temperature firing has been proposed (Korean Patent Publication No. 2004-0063630).

Korean Patent Publication No. 2004-0063630 uses chondroboimide as an inorganic binder similarly to the production method proposed in the present invention, but since zeolite, an inorganic binder, a plasticizer and a lubricant are simultaneously kneaded and molded, There is a disadvantage that the microformability is still insufficient.

The inventors of the present invention found that the viscosity and strength of a dough capable of producing a high specific surface area honeycomb type zeolite extrudate having an extremely fine pore structure with an extruded body thickness of 0.1 to 2 mm between the inner pores ) Were found to be the most important factors determining the fracture toughness and the fracture caused by cracking during drying and heat treatment. (Macrocracks, breakage, etc.) of the molded body produced by the step of performing the gelled gellation are varied, and thus the present invention has been made. Further, it has been found that the gelling of the base state is very effective, and thus the present invention has been proposed.

It is an object of the present invention to overcome the above-mentioned problems that a nitrogen oxide removal efficiency is high at a high temperature (400 ° C), which is a weak point of conventional V ₂ O ₅ / WO ₃ , (MoO ₃ ) / TiO ₂ , A honeycomb type nitrogen oxide reduction zeolite catalyst having a high specific surface area and applicable to a specific nitrogen oxide generation facility (a NO _x generation source including a power plant) that can be used for mobile use and can not use a vanadium catalyst, And a method for treating nitrogen oxide exhaust gas using the catalyst.

In particular, the present invention provides a method for producing a high specific surface area honeycomb type zeolite extrudate having a micropore structure through the addition of pseudoboehmite as an inorganic binder to zeolite and the optimization of the chondroboemite conditions .

A honeycomb type zeolite catalyst for reducing nitrogen oxides having a high specific surface area, a method for producing the catalyst, and a method for treating exhaust gas using the catalyst will be described in detail. Here, unless otherwise defined, technical terms and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention belongs. In the following description, the gist of the present invention is unnecessarily blurred And a description of the known function and configuration will be omitted.

The method for producing a honeycomb catalyst for reducing nitrogen oxides according to the present invention comprises the steps of: (a) mixing a shoebo emulsion, distilled water and a pH adjuster, and uniformly peptizing the mixture to obtain an inorganic binder; (b) kneading the zeolite, the inorganic binder, the organic binder and the distilled water to obtain a dough; (c) extruding the dough into an extrudate having through-pores having a regular structure; And (d) drying the extruded body followed by heat treatment.

As described above, the method for producing a honeycomb catalyst for nitrogen oxide reduction according to the present invention is characterized in that the peptization is carried out in a state where the pseudohemite is mixed with the zeolite and the organic binder and is carried out in an independent step. In step (a), the peptides of the individual pseudo esters of the chitosan are carried out under a controlled pH, a mixed amount of the distilled water adjusted and a controlled peptizing time so as to increase the moldability of the dough in the step (b) Thereby making it possible to produce a honeycomb type zeolite shaped body having a very fine structure. Further, it is possible to prevent the molded article produced by the peeling of the pseudo-emulsion of step (a) from being broken during the drying and heat treatment.

More specifically, if the peptization of the pseudoabomite is too severe, a honeycomb extruded body having a fine pitch (pitch between the centers of the pores) due to excessive shear stress at the time of extrusion can be produced If the pecking of the chitosuboite does not occur sufficiently, the physical strength of the extrudate is too weak to cause the collapse of the shape of the extrudate.

Therefore, it is necessary to highly adjust the degree of peptization, and by this adjustment, a high specific surface area honeycomb type zeolite extrudate having a micro-pore structure having an extruded body thickness of 0.1 to 2 mm between inner pores can be produced.

It is necessary to prepare an inorganic binder through a separate independent peptizing step as in the step (a), not during the mixing of the step (b) for peptizing of highly controlled pseudoboehmite, The pH at which the ging is performed, the amount of distilled water added and the time at which the peptization is performed should be optimized.

When peptizing the shudo boehmite is carried out in the step (b), the honeycomb extruded body having a very fine structure can not be manufactured due to low formability and strength, and the possibility of micro cracking And the fracture rate is increased in the process of drying and heat treating the extruded body.

The pH adjusting agent in step (a) is monovalent acid, ammonium hydroxide, an amine compound, or a mixture thereof. The monohydric acid is preferably acetic acid, nitric acid or a mixed acid thereof, and the amine compound is preferably a primary amine, a secondary amine, or a mixture thereof, and the amine compound is preferably an alcohol amine having an alcohol group. The pH-adjusting agent is preferably used for the peptizing in step (a) in an acid having a pH of from 0.5 to 6 or a base state having a pH of from 8 to 11.

At this time, even if the pH is in the range of 8 to 11, it is preferable to adjust the pH in the presence of monosaccharide such as acetic acid or nitric acid. It is most preferable to adjust the acid state of pH 0.5 to 6 by adding acetic acid, nitric acid or a mixed acid thereof, and the base state of pH 8 to 11 is most preferably adjusted by adding ammonium hydroxide together with acetic acid, nitric acid or mixed acid thereof Do. When the monosaccharide and the base (ammonium hydroxide, amine compound, or a mixture thereof) are added to adjust the pH to a base of 8 to 11, the monosaccharide is added in an amount of 1 to 5 parts by weight per 100 parts by weight of the zeolite Is preferably added.

It is preferable to carry out the reaction under the condition of 100 to 500 parts by weight of distilled water with respect to 100 parts by weight of pseudoboehmite in an acidic or basic state in the range as described above.

At this time, it is preferable that the peptizing is performed for 10 to 40 minutes in an acid having a pH of from 0.5 to 4 or a base state having a pH of from 8 to 11. When the peptizing time is 10 minutes or less or 40 minutes or more in an acid having a pH of 0.5 to 4, particularly an acid having a pH of 0.4 to 3.5 or a pH of 8 to 11, the physical strength of the extrudate is too weak, An extrudate having a shape collapsed or a shape broken due to stress at the time of extrusion is produced.

It is also preferred that the peptizing is carried out for 2 to 4 days in an acid of 4 to 6, in particular an acid of pH 4 to 6. The physical strength of the extrudate is too weak to cause the collapse of the shape of the extrudate, and if it is carried out for more than 4 days, the degree of peptizing of the pseudoboehmite is insignificant.

The degree of dispersion and the particle size of peptized pseudo-ambohemite are controlled through the above-described conditions, and finally the gelated state of the peptized pseudo-pseudomonas is finally obtained.

The inorganic binder containing peptized pseudoboehmite is mixed with the organic binder together with the zeolite under the above conditions. The inorganic binder is mixed with 10 to 150 parts by weight of the inorganic binder, 1 to 15 parts by weight Part of the organic binder and 30 to 100 parts by weight of the distilled water are added and mixed. The mixing can be carried out using a mixing method commonly used for producing an extrusion molded product. After the zeolite and the organic binder are added to perform dry mixing, the inorganic binder and the distilled water It is preferable to carry out secondary wet mixing.

After the mixing is completed, the stamen is preferably performed to obtain more uniform physical properties.

Fiber (fiber) per 100 parts by weight of the mixture during the zeolite or particle (particle) in the form of Si, Al, Ti, Zr, SiO 2, Al 2 O 3, TiO 2, more than one in the ZrO ₂ These minerals 0 to 150 A further weight portion may be added to effect mixing. The inorganic material may further increase the physical strength of the dough in step (b), and the amount of the inorganic material in the range of 0 to 150 parts by weight may be such that the dough has an increased physical strength and does not impair the viscosity suitable for extrusion molding , And does not decrease the characteristics of the catalyst.

In the present invention, the zeolite produced from the honeycomb extrudate can be natural zeolite or artificially synthesized zeolite, and zeolite having various molar ratios of SiO ₂ / Al ₂ O ₃ can be used, but the molar ratio is 25 to 35 .

In addition, the zeolite may be a zeolite in which a metal having activity to nitrogen oxides (hereinafter referred to as an active metal) is ion-exchanged, and a zeolite carrying a metal having an activity.

The active metal is preferably at least one metal selected from transition metals and lanthanides, and more preferably at least one metal selected from Fe, Cu, Co, Pt, V, Ce and Mo.

It is preferable that the zeolite is MFI,?, Y or a mixed type thereof, and MFI,?, Y or a mixed type thereof in which at least one metal selected from Fe, Cu, Co, Pt, V, desirable.

The organic binder may be any of organic binders conventionally added to the inorganic dough for producing the extruded product, but it is preferably an ethyl cellulose group, a methylcellulose group, an ethylcellulose derivative, a methylcellulose derivative, or a mixture thereof More preferably, a methyl cellulose group is used. The organic binder improves the moldability upon extrusion and mitigates cracking during drying.

the inside of the extruder is maintained in a vacuum state during the extrusion of step (c), and is preferably molded at a molding speed of 300 to 500 mm / min. Both the cylindrical extruder and the piston extruder can be used for the extrusion, but it is preferable to use a cylindrical extruder for the continuous process. The forming speed is a condition in which the honeycomb extruder is not damaged by excessive stress applied at the time of extrusion while increasing the production efficiency at a molding speed optimized for the kneading condition of the step (b).

The viscosity and strength of the dough are optimized by the optimized mixing conditions of step (a), optimized mixing conditions and mixing ratio of step (b) of the present invention, so that the round or polygonal shape A honeycomb extruded body having a high specific surface area in which fine pores of a honeycomb structure (sectional shape) are regularly arranged can be obtained. It is possible to obtain an excellent extruded body having a thickness of 0.1 to 2 mm between the pores having the regular structure through the extrusion.

The honeycomb extruded body produced through the extrusion process is dried at a temperature of 100 ° C or less under constant temperature and humidity conditions and calcined at a temperature of 100 to 600 ° C to produce a honeycomb catalyst for reducing nitrogen oxides. In order to prevent cracking due to the heat treatment, it is more preferable to perform a two-stage heat treatment in which a high-temperature heat treatment at 400 to 600 ° C is performed after a low-temperature heat treatment at 100 to 150 ° C.

The exhaust gas containing nitrogen oxide (NOx), which is one or more substances selected from NO, NO ₂ and N ₂ O, and a honeycomb catalyst for reducing nitrogen oxide produced by the above-described production method of the present invention, And the nitrogen oxides can be reduced through the catalytic reaction at 200 to 500 ° C.

At this time, the exhaust gas may contain sulfur dioxide, and the exhaust gas to be in contact with the honeycomb catalyst for reducing nitrogen oxide is not limited, but it is preferable that the exhaust gas has a space velocity of 100,000 / h or less.

The production method of the present invention is advantageous in that a honeycomb catalyst having a regular structure of through-pores can be manufactured in a solid shape and a high yield, and a honeycomb shape having fine through pores and a small space pitch can be manufactured There is an advantage that a catalyst having a high specific surface area can be manufactured. In the treatment of the exhaust gas using the honeycomb catalyst produced by the production method of the present invention, the catalyst characteristics are not lowered by the inorganic binder used, Has a high N ₂ conversion rate of 80% or more at a high temperature of 400 ° C or more, and has a high N ₂ conversion rate of 80% or more at a high temperature of 400 ° C or more.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings and examples, with reference to the accompanying drawings. The following drawings and embodiments are provided as examples so that those skilled in the art can fully understand the spirit of the present invention. Therefore, the present invention is not limited to the following drawings and embodiments, but may be embodied in other forms.

The zeolites used in the following Examples and Comparative Examples are MFI type zeolites obtained by 5% ion-exchanged Fe metal having activity against nitrogen oxides.

(Example 1)

Preparation of a honeycomb catalyst for reducing nitrogen oxides having a pitch of 6.6 mm using peptized pseudoboehmite at pH = 10

330 g of distilled water, 1.5 g of acetic acid (Sigma Aldrich, 99.8% +) and ammonia water having a molar concentration of 16% were added to 100 g of sucrose emulsion (SASOL), the pH was adjusted to 10 and the mixture was stirred for 30 minutes to prepare pseudoboehmite Was performed to prepare an inorganic binder.

15 g of methylcellulose was added to 500 g of MFI type zeolite (S-d-Chemical) and dry mixing was performed. Then, 100 g of the inorganic binder and 400 g of distilled water were added to perform wet mixing. After the wet mixing, the dough was made by performing the stomach.

The extruded product was prepared at a molding speed of 400 mm / min at a cylinder rotation speed of 50 rpm while keeping the inside of the extruder in a vacuum state. The extruded product thus obtained was dried at 65 DEG C for 12 hours and further dried at 80 DEG C for 12 hours. The extruded body dried using a furnace was heat-treated at 120 ° C for 2 hours and then heat-treated at 500 ° C for 3 hours to obtain a nitrogen oxide having a pitch of 6.6 mm A reducing honeycomb type catalyst was prepared. Fig. 2 is a photograph of the extruded product in the drying step. The physical form of the produced honeycomb catalyst for nitrogen oxide reduction is summarized in Table 1 below.

(Table 1)

(Example 2)

Preparation of a honeycomb catalyst for reducing nitrogen oxides having a pitch of 6.6 mm using peptized pseudoboehmite at pH = 1.5

Example 1 was repeated except that nitric acid (Sigma Aldrich, 60% +) was added in place of acetic acid and ammonia water to adjust the pH to 1.5 and then stirred for 20 minutes to prepare an inorganic binder. A honeycomb type catalyst for nitrogen oxide reduction having a pitch of 6.6 mm was prepared.

(Example 3)

Preparation of a honeycomb catalyst for nitrogen oxide reduction with 2.1 mm pitch using peptized pseudoboehmite at pH = 1.5

A honeycomb type catalyst for nitrogen oxide reduction having a pitch of 2.1 mm was produced under the same conditions as in the extrusion, drying and calcination heat treatment of Example 1, using the inorganic binder produced using the nitric acid of Example 2 above. The physical form of the prepared honeycomb catalyst for nitrogen oxide reduction is summarized in Table 2 below.

(Table 2)

(Example 4)

Production of honeycomb catalyst for nitrogen oxide reduction having a pitch of 6.6 mm according to the amount of inorganic binder added

A 30 wt% inorganic binder was added in the same manner as in Example 1 except that 150 g and 200 g of the inorganic binder prepared in Example 1 were added to prepare a dough. A honeycomb type catalyst and a honeycomb type catalyst for reducing nitrogen oxides having a pitch of 6.6 mm added with an inorganic binder of 40 wt% were respectively prepared.

(Comparative Example 1)

Extrusion characteristics of dough without inorganic binder

15 g of methylcellulose was added to 500 g of MFI-type zeolite (s-d-Chemical), dry mixing was performed, and 330 g of distilled water was further added to perform wet mixing. After the wet mixing, the dough was made by performing the stomach. The kneaded product thus obtained was put into a cylindrical extruder, the inside of the extruder was maintained in a vacuum state, and the cylinder was rotated at a rotation speed of 50 rpm at a molding speed of 400 mm / min. As a result, the kneaded product was not extruded into a honeycomb shape To obtain an amorphous extrudate which lost its shape.

(Comparative Example 2)

Extrusion characteristics of peptized pseudoboehmite with strong base (pH = 12)

330 g of distilled water, 330 g of distilled water, 1.5 g of acetic acid, and ammonia water having a molar concentration of 16% were added to 100 g of pseudoboehmite to adjust the pH to 12, followed by stirring for 30 minutes to peptize the pseudoboehmite to prepare an inorganic binder Respectively. FIG. 3 is an optical photograph of a pseudotuberemic peptide in a strong base state. A dough was prepared in the same manner as in Example 1, except that the inorganic binder prepared in Comparative Example 2 was used. The kneaded product thus obtained was placed in a cylindrical extruder, and the inside of the extruder was kept in a vacuum state. The cylinder was rotated at a rotation speed of 50 rpm and extruded at a molding speed of 400 mm / min. As a result, I could not get it.

A test apparatus as shown in FIG. 5 was constructed to measure the exhaust gas treatment performance of the catalyst prepared by the method of the present invention containing nitrogen oxides. In order to construct various kinds of exhaust gases, the gases of N ₂ , O ₂ , NO, and SO ₂ are respectively controlled by MFC and mixed in a gas mixer, and the mixed gas is reacted by a preheater Lt; / RTI > Before the mixed gas with the increased temperature is introduced into the reactor, NH ₃ whose flow rate has been adjusted is injected into the MFC, and the catalyst loaded in the reactor is heated to the reaction temperature, of N ₂ reaction is carried out. The reaction was performed and the gas discharged to the downstream was sampled to evaluate the characteristics of the catalyst. At this time, the reactor is maintained at the reaction temperature, and N ₂ reduction The reaction is carried out.

To this end, the honeycomb catalyst for reducing nitrogen oxide having a pitch of 2.1 mm prepared in Example 3 was cut into a size of 25 mm x 25 mm x 250 mm and the result was shown in Figs. 6 to 8. The detailed test conditions using the test apparatus of FIG. 5 are summarized in Table 3 below.

(Table 3)

6 shows the results of measurement of the NO ₂ : NO ratio of the exhaust gas when 400 ppm of SO ₂ gas was injected and when no SO ₂ gas was injected under the conditions shown in Table 3 above. As can be seen from the results of FIG. 6, in the oxygen atmosphere where no sulfur dioxide gas is injected, the oxidation reaction of NO occurs. When the sulfur dioxide gas is injected, the oxidation reaction of NO is reduced at a low temperature. NO oxidation reaction occurs.

FIG. 7 shows the results of measuring the N ₂ conversion rate of the exhaust gas when the SO ₂ gas was injected at 400 ppm in the condition of Table 3 and when the SO ₂ gas was not injected. As can be seen from the results of FIG. 7, it can be seen that the removal efficiency of nitrogen oxides (NO, NO ₂ ) is increased when sulfur dioxide gas is injected, and it has a high N ₂ conversion rate of 80% or more at a low temperature of 300 ° C. have.

8 is the case without injection of gas of SO ₂ under the conditions of Table 3, the state injection amount of the reaction temperature ammonia gas at fixed with 420 ℃ state, based on the NO of 200 ppm having a 0.6 to 1.7 ratio, exhaust And the N ₂ conversion rate of the gas was measured. As can be seen from the results of FIG. 9, as the amount of ammonia gas is increased, the effect of reducing nitrogen oxide is increased. In particular, when ammonia gas having a ratio of 1.4 or more is introduced, more than 95% of nitrogen oxide is removed.

FIG. 9 is a graph showing the results of measurement of the nitrogen oxide reduction amount of the honeycomb type catalyst for reducing nitrogen oxide with 6.6 mm pitch added with 30 wt% of the inorganic binder prepared in Example 4, after cutting the catalyst, a 6.6mm pitch NOx reduction catalyst having a honeycomb-type prepared in example 1 to a size of 25x25x250mm one mounted to each reactor, rather than injecting a gas of SO ₂ under the conditions of Table 3, And the N ₂ conversion rate of the exhaust gas was measured while the reaction temperature was fixed at 420 ° C. As can be seen from the measurement results of FIG. 9, it can be seen that the reduction characteristics of nitrogen oxides do not decrease even though the amount of the inorganic binder added increases.

Although the present invention has been described in detail with reference to specific embodiments thereof and specific examples thereof, it is to be understood that the same is by way of illustration and example only and is not to be taken by way of limitation, It is to be understood that the invention is not limited thereto and that various modifications and changes may be made thereto by those skilled in the art.

Accordingly, the spirit of the present invention should not be construed as being limited to the embodiments described, and all the equivalents or equivalents of the claims, as well as the claims set forth below, fall within the scope of the present invention will be.

1 is an example of a honeycomb shape manufactured by the manufacturing method of the present invention,

Fig. 2 is an optical photograph of an extrudate of the drying step of Example 1 of the present invention,

3 is an optical photograph of the inorganic binder of Comparative Example 2,

4 is an optical photograph of the extrusion step of Comparative Example 2,

Fig. 5 is a device configuration diagram for measuring exhaust gas treatment characteristics containing nitrogen oxides,

6 shows the result of measuring the NO ₂ : NO ratio of the exhaust gas when 400 ppm of SO ₂ gas was injected and when no injection was performed.

FIG. 7 shows the results of measuring the N ₂ conversion rate of the exhaust gas when 400 ppm of the SO ₂ gas was injected and when the SO ₂ gas was not injected.

8 shows the results of measuring the N ₂ conversion of the exhaust gas according to the amount of the ammonia gas injected under the condition that the reaction temperature was fixed at 420 ° C without injecting SO ₂ gas,

9 shows the results of measuring the N ₂ conversion of the exhaust gas according to the addition amount of the inorganic binder of the present invention.

Claims (16)

(a) mixing Pseudomonas, distilled water and a pH adjuster, and uniformly peptizing the mixture to obtain an inorganic binder; (b) kneading the zeolite, the inorganic binder, the organic binder and the distilled water to obtain a dough; (c) extruding the dough into an extrudate having through-pores having a regular structure; And (d) drying the extruded body followed by heat treatment; Wherein the catalyst is a catalyst for reducing nitrogen oxides. The method according to claim 1, (a) The peptizing is performed by adding 100 to 500 parts by weight of distilled water to 100 parts by weight of pseudoboehmite. 3. The method of claim 2, wherein the peptizing of the shudo boehmite in step (a) is carried out in an acid at a pH of from 0.5 to 6 or in a basic state at a pH of from 8 to 11. 31. A method for producing a honeycomb catalyst for reducing nitrogen oxides, The method of claim 3, wherein the peptizing in step (a) is performed for 10 to 40 minutes in an acid having a pH of from 0.5 to 4 or a base of from 8 to 11. The method of claim 3, wherein the peptizing in step (a) is carried out for 2 to 4 days in an acidic condition of pH 4 to 6. The method according to claim 1, Wherein the pH adjusting agent is selected from one or more selected from the group consisting of monosaccharide; ammonium hydroxide and an amine compound; Or a mixture of said acid and said base. ≪ RTI ID = 0.0 > 11. < / RTI > 5. The method of claim 4, Wherein the base state of the pH 8 to 11 is selected from the group consisting of one or more selected acids in the monovalent group; And at least one selected from ammonium hydroxide and amine compounds. ≪ Desc / Clms Page number 24 > The method according to claim 1, (b) is mixed with 10 to 150 parts by weight of the inorganic binder, 1 to 15 parts by weight of the organic binder and 30 to 100 parts by weight of the distilled water, based on 100 parts by weight of the zeolite. A method for producing a honeycomb type catalyst. The method according to claim 1, wherein the zeolite in step (b) is a zeolite ion-exchanged or supported on at least one metal selected from transition metals and lanthanide groups. 10. The method of claim 9, Wherein the metal is at least one selected from the group consisting of Fe, Cu, Co, Pt, V, Ce, and Mo. The method for producing a honeycomb- The method according to claim 1, (b) the paste is fiber (fiber) per 100 parts by weight of the zeolite of step or particle (particle) in the form of Si, Al, Ti, Zr, SiO 2, Al 2 O 3, TiO 2, more than one in the ZrO ₂ And 0 to 150 parts by weight of the selected inorganic material. The method according to claim 1, wherein the pores of step (c) are pores having a polygonal or circular cross section and penetrating through the long axis of the extrudate. The method according to claim 1, wherein the heat treatment in step (d) is performed at 100 to 600 ° C. The method according to claim 1, Wherein the organic binder is a methylcellulose group. ≪ RTI ID = 0.0 > 11. < / RTI > delete (a) mixing Pseudomonas, distilled water and a pH adjuster, and uniformly peptizing the mixture to obtain an inorganic binder; (b) kneading the zeolite, the inorganic binder, the organic binder and the distilled water to obtain a dough; (c) extruding the dough into an extrudate having through-pores having a regular structure; (d) drying the extruded body followed by heat treatment; And (e) a step of conversion to N ₂ is contacted in step (d) the nitrogen containing the heat-treated extruded body oxide reduction-type honeycomb-type catalyst and a nitrogen oxide and a 200 to 500 ℃ an exhaust gas containing ammonia obtained in Wherein the nitrogen oxide exhaust gas treatment method comprises the steps of:

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